#include <stdio.h>
#include "math.h"


/*
Description: 数学计算

Author：itmojun
E-Mail: dj@itmojun.com
Time: 2023-9-4 13:55

*/


int main()
{
	int s = 0;

	s = 100 * 101 / 2;

	printf("%d\n", s);
	printf("%d\n", fac(3));

	printf("%d\n", sum(1, 2));

	printf("end...\n");

	return 0;
}
